System and mechanism for making ordinary pianos respond to player piano rolls



A. R. GREEN CHANIS Feb. 9, 1960 SYSTEM AND ME M FOR MAKING ORDINARY PIANOS RESPOND TO PLAYER PIANO ROLLS Filed Oct. 24, 1957 United States PatentO SYSTEM AND MECHANISM FOR MAKING ORDI- NARY PIANOS RESPOND TO PLAYER PIANO ROLLS Arthur Robert Green, Cincinnati, Ohio Application October 24, 1957, Serial No. 692,153

24 Claims. (Cl. 84-107) switch arrangement in combination with other mechanism 7 to insure positive performance. 1

In a patent to Meade 1,006,669 there is disclosed the broad concept of having a plurality of switches responsive to atmospheric pressure means so as to energize electrical means for actuating the keys of a piano in response to the perforations on a player piano roll of music. The Meade system seems to include a vacuum producing and switch mechanism which would be very inefficient and which-would require an inordinate amount of power as well as special switch blades which would be difficult and expensive to manufacture. In addition there are other patents in the art which show the broad concept of having piano keys operated by electrical means which include switch fingers which extend through perforations in the roll of music to make contact with a member therebeneath, which arrangements are unduly hard on the roll and cause excessive wear.

A very important object of my invention is to provide a small, compact unit housing most of the primary mechanism by which an ordinary piano may readily be adapted to respond to a roll of player piano music.

Another object of my invention is to provide a unit of the type generally described which can be located at places relatively remote from the piano itself.

A very important object of my invention is to provide an arrangement including the combination of a tracker bar and switch mechanism which is particularly adapted to respond to the player piano roll in a positive and efficient manner.

It is also an object of my invention to provide mechanism whereby the keys of an ordinary piano are operated according to perforations in a roll of player piano music through the use of individual solenoids for the separate keys, which solenoids are actuated by individual wind blast-vacuum operated switches and which mechanism may be manufactured economically and easily installed.

These and other objects of my invention will become apparent to those skilled in the art during the course of the following description as viewed in the light of the objects herein set forth and with reference to the accompanying sheet of drawings, in which drawings like numerals are employed to designate like parts throughout and in which:

Figure 1 is a semi-diagrammatic, side-elevational view of my invention as applied to an ordinary piano in which old and standard elements such as the table on which the unit is mounted and the piano itself are shown in dotted lines,

Figure 2 is a fragmentary perspective view of a modiice partments housing switches for operating the piano keys and other mechanisms,

Figure 3 is a semi-diagrammatic view, with parts taken along a vertical section and parts broken away, showing the principal working parts ofthe invention and the manner in which they are disposed so as to accomplish the objects herein set forth, and

Figure 4 is a fragmentary section taken on the line 44 of Figure 3.

My invention is illustrated as mounted within a housing 10 the contents of which comprises a motor 11, vacuum pump 12, vacuum manifold 13, a series of individual switch compartments 14, a tracker bar 15, conduits 16 extending from the individual perforations of the traccker bar to the individual switch compartments, and rolls 17 and 18 on which is disposed a roll of player piano music 19. There are also connections 20 from the manifold 13 to the individual switch compartments '14. It will be understood that the motor 11 will drive the vacuum pump 12 and the rolls 17 and 18 in conventional manner. As perhaps more clearly shown in Figures 2 and 3 leads from the post 21 will be connected to a common bus bar 22 connected to a power supply generally indicated by the plus and minus terminals 23 and 24. Leads .26, generally similar to those indicated at 25 and extending between the switch post 21 and the bus bar 22, extend from the switch posts 27 and preferably are collected in a single cable 28 extending from the unit to the piano. Electric current through the terminals 23 and 24 may be obtained by use of the conventional plug-in, cord arrangement generally indicated at 29.

At the piano itself there will be installed a separate solenoid generally indicated at 30 for each of the individual piano keys or piano key actions generally indicated at 31. Except as utilized in the general combination there is nothing unique about the solenoids 30 or the piano keys 31. The solenoids 30 are so arranged in the circuit including the power supply as represented by the terminals 23 and 24, the leads 25 and 26, and the switch posts 21 and 27, that upon closing of the circuit by actuation of the switch member 32 the solenoids will contact the piano keys with sufficient force to cause the respective note to be sounded. Extraneous noise may be eliminated by padding the solenoid members as generally indicated at 33.

The general arrangement of the mechanism so far described is such that upon a roll 19 of player piano music being properly disposed about the rollers 17 and 18 and the motor energized so as to drive these rollers and pass the roll of music 19 across the tracker bar 15, this same motor also serving to actuate the vacuum pump to draw a vacuum in the manifold 13 and individual switch compartments connected therewith, the individual perforations denoting the notes to be sounded and located in the roll 19 will match up with corresponding openings 34 in the tracker bar 15. When an opening in the roll of music 19 coincides with an aperture 34 in the tracker bar 15 a blast of air will travel through the conduit means 16 extending from that aperture to its respective switch compartment 14, whereupon the leaf spring member 32 in that particular compartment 14 will effect a connection between the switch posts 21 and 27 thereby to complete a circuit through the respective solenoid 30 which in turn will cause the piano key 31 to be actuated and a note sounded. The perforations in the roll of player piano music 19 may be arranged not only to coincide with apertures 34 in the tracker bar 15 whereby to actuate a piano key solenoid but also there may be apertures to correspond with tracker bar openings for the actuation of other solenoid switches. Thus it will be understood that the unit 10 may include conventional rewind mechanism and a rheostat for varying the power. supplied to the various solenoids depending on the location of such additional perforations or openings in the roll 19 with respect to those perforations or openings which govern the actuation of piano key solenoids. In addition there may be separate solenoids provided for the piano foot pedals whereby certain of the notes may be held for varying lengths of times depending upon the location of still other openings in the roll of player piano music. Thus, considering Figure 2, the switch compartment 14a may be thought of as being in a circuit including a solenoid to actuate the rewind mechanism, the compartment 141: in a circuit to effect actuation of a foot pedal for holding notes, the compartment 140 in a circuit to actuate a solenoid for varying the rheostat as required for sounding certain notes softer or louder as desired and the compartment 14d in a circuit including the key at one end of the piano keyboard. It will also be apparent to those skilled in the art that other perforations and switch compartments plus appropriate leads and solenoids to effect actuation of other mechanism such as, for example, a switch to prevent actuation of the piano key solenoids during those times when no player piano roll is mounted within the unit may be provided.

It is also pointed out that the power supply will be sufiiciently large to keep a maximum of twelve of the solenoids 30 at their maximum energization when all twelve are energized simultaneously. The individual solenoids will be of such construction as to adequately handle the electrical energy passed therethrough when only one solenoid is actuated at a time. This electrical condition is dictated by the number of keys that can be played at a time. and is conventional in nature.

Referring again to Figures 2 and 3, I have illustrated a switch member 32 as comprising a leaf spring having an oifset'portion 35 to the underside of which is fastened a piece of fibrous material 36. The spring is mounted at 37 so that a blast of air entering the switch cornpartment, through the orifices 388 will, aided by the section drawn through the passage 20, cause the fibrous member 36 to seat on the bottom of the switch compartment 14 and close the aperture 39. The member 32, of course, will be made of a good conductor of electricity and preferably has a contact button 40 mounted thereon for engagement with the switch post 27. The post 27 and floor of compartment 14 are threaded so that the air gap between the contact button 40 and inner end of the post 27 may easily be adjusted. The aforementionedblast of air will travel through the conduit 16 as occasioned by the coinciding of an opening in the roll of music 19 with an aperture 34 in the tracker bar 15.

l have illustrated two means by which the air entering the tracker bar aperture 34 as governed by the perfortions in the roll of music 19 may be got to the respective switch compartment 14. In Figure 2 I have illustrated the conduit 16 as comprising a plurality of individual tubes. In the arrangement of Figure 3 I have shown the conduit 16 as comprising a member containing a plurality of channels or passageways 41. In this latter arrangement the member 1612 which contains the passageways 41 may be east along with the tracker bar a as a single unit.

Regardless of whether it is the individual tubes or the member with the channels therein which are utilized, it is quite desirable for the aperture 38 to be located on a line extending through the switch member 35 and aperture 39 so that the blast of air is most effectively delivered. The switch member or leaf spring 32 should be of such resiliency that when there is no roll perforation in alignment with the respective tracker bar aperture 34, the member 32 will be in the position illustrated in Figure 3 and the contact button 40 removed from the end of the switch post 27. The member 32, however, must also be. of such resiliency as to be completely responsive to that condition wherein a, player piano roll perforation is in alignment with the tracker bar aperture 34 for the particular compartment 14 in question so that the blast of air thus drawn through the roll, conduit 16 (passageway 41 in Figure 3) and compartment 14, by reason of the action of the vacuum pump 12 working through the manifold 13 and conduits 20, will quickly and positively bring the member 36 against the aperture 39 and the contact button 40 against the switch post 27 whereby to complete a circuit through the particular solenoid 30 involved.

The use of the individual switch compartments 14 makes for a very efiicient device and reduces to a minimum the requirements of the vacuum pump and motor. The combination of the wind blast and suction on the end 35 or the leaf spring or switch member 32 is most effective and highly desirable. By having the switch effectively close and seal the exhaust port 39 each time a solenoid is to be actuated I effect a great saving in the vacuum arrangement. By using the conduit means 16 I am able to effect variations in the location of the switch compartments 14 with respect to the tracker bar 15.

It is believed that the operation of my invention has been clearly set forth in the above description. From this it will be apparent to those skilled in the art that modifications may be made in my invention without departing from its scope and spirit. Itis to be understood that while I have shown my invention as embodied in certain particular arrangements and structures, I do not intend to be limited to such arrangements and structures except insofar as they are specifically set forth in the subjoined claims.

Having thus described my invention what I claim as new and what I desire to protect by United States Letters Patent is:

1. A unit by which an ordinary piano may be made to respond to a roll of conventional player piano music, which comprises: a tracker bar, means to pass the roll of music over the tracker bar, said tracker bar having apertures to coincide with perforations in said roll of music, a plurality of individual switch compartments, means to draw a vacuum in said compartments, said means to draw a vacuum connecting with exhaust ports in the compartments, conduits extending between said compartments and said tracker bar apertures, electric power supply means, a normally open switch in each of said switch'compartments, circuits including said electric power supply means and said normally open switches, each of said switches including a member responsive to a blast of air drawn into a respective compartment through a said conduit and a said aperture and a said perforation and a said exhaust port by said means to draw a vacuum, whereby to close a said circuit, and means to close a said exhaust port when a said circuit is closed, individual solenoids for each of the separate piano keys, and leads connecting said solenoids to said circuits.

2. The unit of claim 1 in which a said member within a said switch compartment comprises a leaf spring.

3. The unit of claim 2 in which one end of said leaf spring is fastened within said compartment and the other end is free thereof, a said conduit terminating at an entrance port provided in said compartment adjacent the free end of said leaf spring.

4. The unit of claim 3 in which the exhaust port provided in each compartment is adjacent the free end of said leaf spring. I

5. The unit of claim 4 in which said leaf spring is provided with the said means to close said exhaust port when a blast of air is drawn through said entrance port.

6. The unit of claim 5 in which said leaf spring is provided with a contact button to close a said circuit only when said exhaust port is closed.

7 The unit of claim 1 in which said conduits comprise a plurality of individual tubes.

8. The unit of claim 1 in which said conduits comprice a plurality of passageways in a common member.

9. A wind switch comprising a compartment, said compartment having an entrance port and an exhaust port, a circuit closing member responsive to a blast of air entering said compartment through said entrance port, and means to close said exhaust port when said circuit closing member responds to said blast of air.

10. The switch of claim 9 in which said member comprises a leaf spring having one end fastened within said compartment and having its other end free therewithin.

11. The switch of claim 10 in which said entrance port is located adjacent the free end of said leaf spring.

12. The switch of claim 11 in which said exhaust port is located adjacent the free end of said leaf spring.

13. The switch of claim 12 in which said leaf spring is provided with the said means to close said exhaust port.

14. The switch of claim 13 in which said leaf spring is provided with circuit closing means effective only when said exhaust port is closed.

15. The combination of a tracker bar having an aperture to coincide with the note designating perforation of a roll of player piano music, a switch compartment, said compartment having an air entrance port and an air exhaust port, a circuit closing member in said compartment responsive to air movement, a conduit between said aperture and said air entrance port of said compartment for conducting air through a said perforation into direct contact with said circuit closing member, and means to close said air exhaust port when said circuit closing member responds to said air movement.

16. The combination of claim 15 in which said conduit comprises a tube.

17. The combination of claim 15 in which said conduit comprises one of a plurality of passage ways located in a common member.

18. The combination of claim 15 in which said circuit closing member comprises a leaf spring.

19. The combination of claim 18 in which one end 6 of said leaf spring is fixed within said switch compartment and the other end is free thereof, said air entrance port being adjacent the free end of said leaf spring.

20. The combination of claim 19 in which said exhaust port is adjacent the free end of said leaf spring.

21. The combination of claim 20 in which said leaf spring is provided with the said means to close said exhaust port when air is conducted into said switch compartment through said entrance port.

22. The combination of claim 21 in which said leaf spring is provided with a contact button to close a circuit only when said exhaust port is closed.

23. The combination of claim 22 in which said switch compartment includes a post in said circuit to be contacted by said button, said post being adjustable to vary the air gap between said post and said button.

24. In apparatus for making an instrument respond to the perforations in a roll of sheet material, the combination of a tracker bar having apertures to coincide with the perforations in said roll of sheet material, a switch compartment for each of said apertures, each said compartment having an air entrance port and an air exhaust port, a circuit closing member in each said compartment responsive to air movement, a conduit between each said aperture and the air entrance port of its respective compartment for conducting air through a said perforation into direct contact with said circuit closing member, and means to close each said air exhaust port when each said circuit closing member responds to said air movement.

References Cited in the file of this patent UNITED STATES PATENTS 589,535 Pain Sept. 7, 1897 FOREIGN PATENTS 441,602 France Mar. 12, 1912 

